Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Ann Maxillofac Surg ; 12(1): 5-10, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36199459

RESUMO

Introduction: The incidence of infection and scarring in intraoral raw wounds are decreased when wounds are grafted with biological materials. The favourable results of many studies about amniotic membrane in wound healing inspired us to investigate the effects of lyophilised amniotic membrane in intaoral surgical defects. The aim of this study was to evaluate the healing of oral mucosal defects after application of lyophilised amniotic membrane (AM). Methods: Fifteen patients with oral precancerous lesions were included in this study. Lyophilised amniotic membrane was applied to the intraoral surgical defect, after wide excision of the lesion. The effectiveness of the lyophilised AM was evaluated by scoring the following parameters operability, haemostatic status, pain, feeding situation, epithelialisation, change in mouth opening, mucosal suppleness and safety. Results: The lyophilised amniotic membrane has been found to be effective in this study after evaluation of the parameters. No infection or allergic reaction was noticed after application of the lyophilised amniotic membrane in intraoral surgical defects. Discussion: In our study, the size and site of the surgical defect influenced the scar contracture so we suggest lyophilised AM may not prevent scarring for extensive surgical defects. All other findings regarding the effectiveness of lyophilised amniotic membrane in oral wound healing are in accordance with the findings of other studies conducted on hyperdry and cryopreserved AM. Conclusion: Within the limitations of the study, the results showed that the lyophilised amniotic membrane is a cost effective material for immediate coverage of the intraoral surgical defects.

2.
Org Biomol Chem ; 20(26): 5249-5253, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35730444

RESUMO

A new strategy for access to spirocyclopentenonyl oxindole frameworks is disclosed. Suitably anchored furfuryl alcohol at C3 of an oxindole was used for the aza-Piancatelli rearrangement, which furnished spirocyclic aminocyclopentenone frameworks with catalytic phosphomolybdic acid. The scope of the transformation was extended to the carbo-Piancatelli rearrangement with various indole derivatives.


Assuntos
Carvão Vegetal , Catálise , Oxindóis , Estereoisomerismo
3.
Org Biomol Chem ; 20(18): 3737-3741, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35468177

RESUMO

Herein, the asymmetric and chemoenzymatic synthesis of (R)-nodulone C, cis-nodulone D and related (R)-dihydronaphthalenone is reported. It involves multistep chemical synthesis of putative biosynthetic substrates followed by regio- and stereoselective reduction using a NADPH-dependent tetrahydroxynaphthalene reductase of Magnaporthe grisea to obtain chiral nodulones in a biomimetic fashion.


Assuntos
Magnaporthe , Oryza , Naftóis , Oxirredutases , Pyricularia grisea
4.
Plants (Basel) ; 11(4)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35214848

RESUMO

Capsicum is one of the most perishable fruit which undergo rapid loss of commercial value during postharvest storage. In this experiment our aim is to evaluate the effect of photoactivated TiO2 nano-particle complexed with chitosan or TiO2-nanocomposite (TiO2-NC) on extension self-life of Capsicum fruit and its effect on related morphological, physiological and molecular attributes at room temperature (25 °C). Initially, TiO2-NC coated fruits recorded superior maintenance of total soluble solids accumulation along with retention of firmness, cellular integrity, hydration, color etc. On the extended period of storage, fruit recorded a lower bioaccumulation of TiO2 in comparison to metallic silver over the control. On the level of gene expression for ethylene biosynthetic and signaling the TiO2-NC had more regulation, however, discretely to moderate the ripening. Thus, ACC synthase and oxidase recorded a significantly better downregulation as studied from fruit pulp under TiO2-NC than silver. On the signaling path, the transcripts for CaETR1 and CaETR2 were less abundant in fruit under both the treatment when studied against control for 7 d. The reactive oxygen species (ROS) was also correlated to retard the oxidative lysis of polyamine oxidation by diamine and polyamine oxidase activity. The gene expression for hydrolytic activity as non-specific esterase had corroborated the development of essential oil constituents with few of those recorded in significant abundance. Therefore, TiO2-NC would be reliable to induce those metabolites modulating ripening behavior in favor of delayed ripening. From gas chromatography-mass spectrometry (GC-MS) analysis profile of all tested essential oil constituents suggesting positive impact of TiO2-NC on shelf-life extension of Capsicum fruit. Our results indicated the potentiality of TiO2-NC in postharvest storage those may connect ethylene signaling and ROS metabolism in suppression of specific ripening attributes.

5.
Org Biomol Chem ; 19(25): 5624-5631, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34100039

RESUMO

The N-sulfonyl spiroaziridine oxindole is a recently developed versatile precursor in the synthesis of a wide range of 3,3-disubstituted spirooxindoles. It is usually prepared in three steps from isatin and needs costly and hardly available sulfinimides and hazardous peracid. A sequential and one-pot direct strategy for the synthesis of terminal N-sulfonyl spiroaziridine oxindoles has been developed under ambient conditions with excellent yields (up to 95%) from easily accessible spiroepoxy oxindoles by regioselective amination with aqueous ammonia and a subsequent ring enclosure reaction of the resulting 1,2-amino alcohol using easily available sulfonyl chloride and a base. Other salient features of the protocol include inexpensive substrate requirement and the ease of isolation of the desired product by performing single column chromatographic purification after two consecutive steps.

6.
ACS Omega ; 6(15): 9975-9981, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-34056152

RESUMO

The search for suitable strategies to manufacture self-healable nitrile rubber (NBR) composites is the most promising part in the industrial field of polar rubber research. In recent years, some important strategies, specifically, metal-ligand coordination bond formation, ionic bond formation, and dynamic hydrogen bond formation, have been utilized to develop duly self-healable NBR composites. This paper reviews the continuous advancement in the research field related to self-healable NBR composites by considering healing strategies and healing conditions. Special attention is given to understand the healing mechanism in reversibly cross-linked NBR systems. The healing efficiency of a cross-linked NBR network is usually dependent on the definite interaction between functional groups of NBR and a cross-linking agent. Finally, the results obtained from successful studies suggest that self-healing technology has incredible potential to increase the sustainability and lifetime of NBR-based rubber products.

7.
Plant Physiol Biochem ; 163: 55-67, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33812227

RESUMO

We investigated the combined effect of chitosan (CHT) and putrescine (PUT) on the postharvest shelf life of Capsicum fruit concerning the metabolism of reactive oxygen species (ROS) through direct and indirect effects on ripening characters cell wall hydrolyzing enzyme and ROS metabolism. The PUT and CHT directly affected quality indices like color, firmness and water loss with a concomitant oxidative bust in the development of O2•- and H2O2 in fruit pulp. This was accompanied by significant suppression of respiratory flux, a decrease of total soluble solids and ascorbic acid content throughout postharvest storage. PUT applied with CHT modified the oxidative metabolism of fruits by a significant reduction in the level of O2•- and H2O2 content. In addition, a significant accumulation of total polyamine under respective treatment was reasonably correlated with both ROS producing enzyme as well as H2O2 and O2•-. Wall hydrolyzing enzymes like pectin methyl esterase and cellulase had marked downregulation both under PUT and CHT + PUT treatment. Moreover, on close observation, the combinational effects of PUT and CHT had better effects in the regulation of those enzymes as compared to individual treatment. Fruits restore higher antioxidative capacities as evident with superoxide dismutase (SOD), guaiacol peroxidases (GPX), ascorbate peroxidase (APX) catalase (CAT), glutathione peroxidase (GPX), NADPH oxidase (NOX) and glutathione reductase (GR), indicating their roles on fruit coat softening. Finally, the treatment of PUT and CHT in combination increased shelf life vis-à-vis the quality of fruit.


Assuntos
Quitosana , Frutas , Antioxidantes , Ascorbato Peroxidases , Catalase , Peróxido de Hidrogênio , Putrescina , Espécies Reativas de Oxigênio , Superóxido Dismutase
8.
Polymers (Basel) ; 12(2)2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32046027

RESUMO

In the present study, the suitability of various chemical treatments to improve the performance of jute fibers (JFs) filled natural rubber (NR) composites was explored. The surface of JFs was modified by three different surface treatments, namely, alkali treatment, combined alkali/stearic acid treatment and combined alkali/silane treatment. Surface modified JFs were characterized by X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) spectroscopy and field emission scanning electron microscopy (FESEM). The reinforcing effect of untreated and surface treated JFs in NR composites was comparatively evaluated in terms of cure, mechanical, morphological and thermal properties. Combined alkali/silane treated JFs filled NR composite showed considerably higher torque difference, tensile modulus, hardness and tensile strength as compared to either untreated or other surface treated JFs filled NR systems. A crosslink density measurement suggested effective rubber-fibers interaction in combined alkali/silane treated JFs filled NR composite. Morphological analysis confirmed the improvement in the interfacial bonding between NR matrix and JFs due to combined alkali/silane treatment allowing an efficient "stress-transfer" mechanism. As a whole, combined alkali/silane treatment was found to be most efficient surface treatment method to develop strong interfacial adhesion between NR matrix and JFs.

9.
Mol Biol Rep ; 45(5): 663-673, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29872937

RESUMO

The present work is emphasised with the herbicidal tolerance of Azolla pinnata R.Br. and its modulation with TiO2 nano-particle. Both carbohydrate and nitrogen metabolism were effected with 2,4-D as herbicide and in few cases TiO2-NP had recovered few detrimental effects. From the nutrient status in Azolla it recorded the recovery of nitrogen as well as potassium by TiO2-NP but not in case of phosphorus. However, a conversion of nitrate to ammonium was more induced by TiO2-NP under herbicidal toxicity. Similar results were obtained for inter-conversion of amino acid-nitrate pool, but no changes with glutamine synthase activity with TiO2-NP. Initially, the effects of 2,4-D was monitored with changes of chlorophyll content but had not been recovered with nanoparticle. Photosynthetic reserves expressed as both total and reducing sugar were insensitive to TiO2-NP interference but activity of soluble and wall bound invertase was in reverse trend as compared to control. The 2,4-D mediated changes of redox and its oxidative stress was ameliorated in plants with over expressed ADH activity. As a whole the Azolla bio system with TiO2 supplementation may be useful in sustenance against 2,4-D toxicity through recovery of nitrogen metabolism. Thus, Azolla-TiO2-NP bio system would be realised to monitor the herbicidal toxicity in soil and its possible bioremediation.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Gleiquênias/fisiologia , Titânio/metabolismo , Biodegradação Ambiental , Clorofila/metabolismo , Nanopartículas Metálicas , Nanopartículas , Nitrogênio/metabolismo , Oxirredução , Estresse Oxidativo/fisiologia , Fotossíntese , Potássio/metabolismo , Poluentes Químicos da Água
10.
Chin J Traumatol ; 19(4): 239-43, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27578384

RESUMO

Gunshot injuries are always known to cause severe morbidity and mortality when head and neck are involved. They vary in morbidity, which can occur in civilian surroundings. The wound largely depends on the type of weapon, mass and velocity of the bullet, and the distance from where it has been shot. Close-range gunshot wounds in the head and neck region can result in devastating aesthetic and functional impairment. The complexity in facial skeletal anatomy cause multiple medical and surgical challenges to an operating surgeon, demanding elaborate soft and hard tissue reconstruction. Here we presented the successful management of three patients shot by short-range pistol with basic life support measures, wound management, reconstruction and rehabilitation.


Assuntos
Traumatismos Faciais/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Ferimentos por Arma de Fogo/cirurgia , Adolescente , Adulto , Criança , Traumatismos Faciais/reabilitação , Humanos , Masculino , Ferimentos por Arma de Fogo/reabilitação
11.
Contemp Clin Dent ; 7(1): 111-3, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27041915

RESUMO

Aneurysmal bone cyst (ABC) is a nonneoplastic rare pathologic entity of the jaws. Its locally aggressive nature and high recurrence rate after curettage make surgical resection a better treatment option. Here, we present a case of ABC of maxillary alveolus and its management by alveolectomy followed by white head varnish pack application in the surgical defect.

12.
J Maxillofac Oral Surg ; 14(1): 90-100, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25729232

RESUMO

BACKGROUND AND OBJECTIVES: The main objective is to study and compare the sedative and analgesic effects of intramuscular injection fortwin-phenergan along with local anesthetic and normal saline placebo along with local anesthetics in mandibular third molar surgery. We also assessed and compared the postoperative experience of the patient in relation to the pain intensity, time to first analgesic taken and total number of analgesics consumed over a period of 48 h in the two groups. MATERIALS AND METHODS: Patients who came to the Department of Oral and Maxillofacial Surgery, The Regional Dental College; with complaints regarding mandibular third molar were chosen for the treatment. Patients were evaluated using Corah Dental Anxiety Scale (CDAS) and those patients having a score of CDAS 13 and above were selected. Sixty patients were selected out of which 30 patients formed group 1 and another 30 patients group 2. The patients were randomly divided with flip method into group 1 (study group) and or group 2 (controlled group). RESULTS: Our study results showed that the operating conditions for both the groups at the end of surgery were similar without significant difference. Most of the surgical procedures were graded as excellent and good in both the groups except that difficulty was encountered in two patients from group 1 and one from group 2. CONCLUSION: It could be concluded that particular drugs do not have much influence on the surgical procedure in our study, but it was found that patients from group 1 were more cooperative as compared to group 2 when difficulty was encountered during the surgical procedure.

13.
Nanotechnology ; 24(12): 125702, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23459239

RESUMO

Large scale high yield cadmium sulfide (CdS) nanowires with uniform diameter were synthesized using a rapid and simple solvo-chemical and hydrothermal route assisted by the surfactant cetyltrimethylammonium bromide (CTAB). Unique CdS nanowires of different morphologies could be selectively produced by only varying the concentration of CTAB in the reaction system with cadmium acetate, sulfur powder and ethylenediamine. We obtained CdS nanowires with diameters of 64-65 nm and lengths of up to several micrometers. A comparative study of the optical properties of ferroelectric liquid crystal (FLC) Felix-017/100 doped with 1% of CdS nanowires was performed. Response times of the order of from 160 to 180 µs, rotational viscosities of the order of from 5000 to 3000 mN s m(-2) and polarizations of the order of from 10 to 70 nC cm(-2) were measured. We also observed an anti-ferroelectric to ferroelectric transition for CdS doped FLC instead of the ferroelectric to paraelectric transition for pure FLC.

14.
Br J Oral Maxillofac Surg ; 48(3): 203-4, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19910088

RESUMO

Lipoma of the parotid gland is a rare clinical entity. Because of the rarity, they are not often considered in the differential diagnosis of parotid tumors. Lipoma of the parotid gland constitutes around 3% of all parotid tumors. These are asymptomatic and occur both in the deep and the superficial lobe of the parotid.(1) The most favored age group is from the fifth to sixth decade of life and is 10 times more common in the males.(6) Lipoma extending from superficial to deep lobe of parotid gland has not been reported in the literature to our knowledge till date. A 56-year-old male patient, with this relatively rare parotid gland lipoma is reported in this article; it was managed by conservative superficial parotidectomy preserving facial nerve that, if performed correctly, excludes the possibility of any second attack.


Assuntos
Lipoma/patologia , Neoplasias Parotídeas/patologia , Tecido Adiposo/patologia , Tecido Conjuntivo/patologia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Glândula Parótida/patologia
15.
J Maxillofac Oral Surg ; 9(2): 205-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22190789

RESUMO

Pleomorphic adenoma is the benign tumor of salivary glands, which originates from the myoepithelial cells and intercalated duct cells. This tumor is more common in major salivary glands. This case report describes a rare and unusual lesion in a 55-year-old female, which was diagnosed as pleomorphic adenoma of the minor salivary glands in the upper lip. The tumor was a circumscribed, submucosal nodule, about 2.0 cm in diameter and was characterized by slow growth and rubbery consistency. Complete excision was performed and the histopathological analysis showed an epithelial salivary gland tumor with islands of plasmacytoid cells, duct like structures, in a variable stroma with chondroid, fibrous and myxoid appearance. No recurrence was observed 1 year after the surgery.

16.
J Maxillofac Oral Surg ; 9(4): 420-3, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22190837

RESUMO

Pleomorphic adenoma is a benign tumor of the salivary glands that has elements of both epithelial and mesenchymal tissues. The tumor most commonly arises in the parotid or submandibular glands. Infrequently, it may arise from the minor salivary glands and present as an intraoral mass over the palate or lip. We report a patient with PA over the hard palate, which resembled common intraoral diseases like oral papilloma, squamous cell carcinoma and condyloma acuminate.

17.
Artigo em Inglês | MEDLINE | ID: mdl-16731379

RESUMO

A case of long-standing, bilateral dislocation of the temporomandibular joint characterized by anterior open bite, and an inability to close the mouth is reported. A number of conventional modalities were tried unsuccessfully to reduce the dislocated condyle. Subsequently, the patient was successfully treated with bilateral vertical-oblique osteotomy of ramus (external approach) without using internal fixation. This modality resulted in achieving occlusion and a good range of mandibular movement postoperatively.


Assuntos
Mandíbula/cirurgia , Côndilo Mandibular/patologia , Procedimentos Cirúrgicos Bucais/métodos , Transtornos da Articulação Temporomandibular/cirurgia , Adulto , Humanos , Luxações Articulares/complicações , Luxações Articulares/cirurgia , Masculino , Côndilo Mandibular/cirurgia , Mordida Aberta/etiologia , Mordida Aberta/cirurgia , Osteotomia/métodos , Amplitude de Movimento Articular , Transtornos da Articulação Temporomandibular/complicações
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...